To be honest I don't see the messaging element of PA a problem too much. Yes there's discord, irc, slack, telegram, whatsapp but all of that is down to preference of a particular person or alliance. Trying to put these communities into a single box wont happen (people left irc for a reason?). However I think things like the forum need a good upgrade. They just feel ancient and really you get 0 feedback coming through from this place to make your audience sticky to the site and wanting to keep coming back to check up on whats happening.
Even switching forum software would help in my opinion. Make it look more modern, engaging and welcoming.
https://www.discourse.org/ seems to be quite popular with most companies at the moment.